QApplication uncatched exception: reimplement notify()

[sofian]

There was an error in KDTree line 55 that was making the application crash. Here's the faulty line:

  addPlug(_VIDEO_OUT = new PlugOut<VideoRGBAType>(this, false, "ImgOUT"));

The problem was that the second argument of PlugOut constructor should have been a string and not a boolean. The exception comes from std::string but the real problem is that I got the following error:

Qt has caught an exception thrown from an event handler. Throwing
exceptions from an event handler is not supported in Qt. You must
reimplement QApplication::notify() and catch all exceptions there.

terminate called after throwing an instance of 'std::logic_error'
  what():  basic_string::_S_construct null not valid
Aborted

It speaks for itself: we need to "reimplement QApplication::notify() and catch all exceptions there".